The present invention relates to programming settings of an IC chip and more particularly to programming settings of an IC chip from the pins of the IC chip, rather than at wafer level.
FIG. 1A shows an Intelligent Power Switch, having IN, VDD, OUT and ST pins. In a normal mode, a signal at IN pin turns on a power switch Q1, which, for example, can be a MOSFET. OUT pin connects first of two power terminals of the power switch Q1 of the Intelligent Power Switch to a load and VDD pin connects the second power terminal of the power switch Q1 to a power source. ST pin connects the circuitry of the Intelligent Power Switch to the ground. The internal circuits of the Intelligent Power Switch include a driver 2, connected to a control terminal of the switch Q1 for controlling the switch, as well as other protective circuits for protecting the switch Q1 in the event of short circuit, over-current, over-temperature, and other failures.
What is needed is an ability to program the Intelligent Power Switch without requiring dedicated programming pins, i.e., using existing pins of the Intelligent Power Switch IC.